Quantities, negligible concept

In the real world, 1 like to compare this negligible concept to finding a dollar in the street. If you have no money at all, then that dollar represents a sizable quantity of cash (perhaps your next meal). But if you re a multimillionaire, then that dollar doesn t represent much at all. It may as well be a piece of scrap paper. You may not even pick it up. (I really can t imagine being that rich.) Its value is negligible when compared to the rest of your wealth. This is what I m saying with respect to the volume of the gas particles — sure, they have a volume, but it s so small that it s insignificant when compared with the distance between the gas particles and the volume of the container. 

The concept of a quantity being negligible is used a lot in chemistry. An example is in Chapter 12 where 1 use the acid ionization constant (K ) of a weak acid, ignoring the amount of weak acid that has ionized compared to the initial concentration of the acid. 

On the Stand (Legal Issues and Questions) In methamphetamine and similar cases in which diluted samples are encountered, the forensic chemist may be asked about "usable quantity." In some jurisdictions, the prosecution is required to prove not only that the defendant had a controlled substance, but that the amount possessed was usable. This concept is abo referred to as "measurable quantity." Since quantitation of the methamphetamine femily b not routinely performed, a concentration or percentage value of purity b not always available. The defense may argue that the amoimt present was so small as to be negligible or harmless. Because exhibits are received with low concaitrations of the controlled substance, this b a reasonable question. 

The four quantities above can be determined systematically and automatically by a software, whatever the adsorbent in the presence of micropores, they should all be meaningful, whereas in their absence the derived micropore capacity should simply be negligible. It is only in the latter case that the concept of BET monolayer content can be restored and used without ambiguity. 

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